I started looking around for examples on how to ensure that GDAL was configured and working correctly, and had more success. To add mr sid filed to the map i had to download the pre-compiled version of dot spatial (x64 or x86 as appropriate). I then had
to download and build the test projects, and then copy the example map exe file from the debug project into the root folder of the downloaded executable. I found a reference to the most recent visual studio project file haveing some incorrect settings, and
this must be the cause of the problems i was having.